Pachyonychia congenita

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ORPHA:2309OMIM:167200Q84.5
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2Active trials7Specialists8Treatment centers

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UniteRare data is sourced from FDA.gov, ClinicalTrials.gov, Orphanet, OMIM, and NORD.
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Overview

Pachyonychia congenita (PC) is a rare genetic disorder of keratinization that primarily affects the nails, skin, oral mucosa, and other ectodermal tissues. It is caused by mutations in genes encoding keratin proteins (KRT6A, KRT6B, KRT6C, KRT16, and KRT17) that are essential for the structural integrity of epithelial cells. The condition was historically classified into two main types — PC-1 (Jadassohn-Lewandowsky type) and PC-2 (Jackson-Lawler type) — but is now more commonly categorized by the specific gene affected (e.g., PC-K6a, PC-K6b, PC-K16, PC-K17). The hallmark features of pachyonychia congenita include severely thickened and dystrophic nails (pachyonychia), painful plantar keratoderma (thickened skin on the soles of the feet that can be extremely debilitating and is often considered the most burdensome symptom), oral leukokeratosis (white plaques on the oral mucosa), and follicular keratoses (bumps around hair follicles). Additional features may include palmar keratoderma, cysts (including steatocystomas and pilosebaceous cysts), hyperhidrosis (excessive sweating) of the palms and soles, and natal or prenatal teeth. The plantar pain associated with PC can be severe enough to significantly impair mobility and quality of life, often requiring the use of assistive devices. There is currently no cure for pachyonychia congenita. Treatment is symptomatic and supportive, focusing on management of pain and reduction of thickened skin and nails. Approaches include careful mechanical debridement of thickened nails and calluses, use of topical keratolytics, pain management strategies, and appropriate footwear modifications. Research into targeted therapies, including small interfering RNA (siRNA) approaches aimed at silencing the mutant keratin allele, has shown promise in clinical studies. The International Pachyonychia Congenita Consortium (IPCC) and the patient advocacy organization PC Project maintain registries and support ongoing research efforts.

Also known as:

Clinical phenotype terms— hover any for plain English:

Palmoplantar blisteringHP:0007446Onychogryphosis of toenailsHP:0008401Lower limb painHP:0012514Hyperplastic callus formationHP:0030268Oral leukoplakiaHP:0002745Palmoplantar hyperhidrosisHP:0007410Linear arrays of macular hyperkeratoses in flexural areasHP:0007490Follicular hyperkeratosisHP:0007502Palmar hyperkeratosisHP:0010765Steatocystoma multiplexHP:0012035Cutaneous cystHP:0025245Onychogryphosis of fingernailHP:0040036Fingernail dysplasiaHP:0100798Epidermoid cystHP:0200040Natal toothHP:0000695ParonychiaHP:0001818Advanced eruption of teethHP:0006288
Inheritance

Autosomal dominant

Passed on from just one parent; each child has about a 50% chance of inheriting it

Age of Onset

Neonatal

Begins at or shortly after birth (first 4 weeks)

Orphanet ↗OMIM ↗NORD ↗

FDA & Trial Timeline

3 events
Mar 2025Efficacy and Safety of Bezafibrate 400 mg and Bezafibrate 200 mg as Adjunctive Treatments in Patients With Primary Biliary Cholangitis and Non-optimal Biochemical Response to Ursodeoxycholic Acid Therapy

Assistance Publique - Hôpitaux de Paris — PHASE3

TrialRECRUITING
Nov 2022A Study Evaluating the Safety and Pharmacokinetics of QTORIN Rapamycin 3.9% Anhydrous Gel in the Treatment of Adults With Pachyonychia Congenita

Palvella Therapeutics, Inc. — PHASE3

TrialRECRUITING
Apr 2004International Pachyonychia Congenita Research Registry

Pachyonychia Congenita Project

TrialRECRUITING

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Treatments

No FDA-approved treatments are currently listed for Pachyonychia congenita.

2 clinical trialsare actively recruiting — trials can provide access to cutting-edge therapies.

View clinical trials →

Clinical Trials

2 recruitingView all trials with filters →
Phase 31 trial
A Study Evaluating the Safety and Pharmacokinetics of QTORIN Rapamycin 3.9% Anhydrous Gel in the Treatment of Adults With Pachyonychia Congenita
Phase 3
Actively Recruiting
· Sites: New Brighton, Minnesota · Age: 1699 yrs
Other1 trial
International Pachyonychia Congenita Research Registry
Actively Recruiting
PI: C. David Hansen, MD (Pachyonychia Congenita Project) · Sites: Salt Lake City, Utah

Specialists

7 foundView all specialists →
JM
Joyce Teng, MD
PALO ALTO, CA
Specialist
PI on 3 active trials
CM
Christophe Corpechot, MD
Paris
Specialist

Rare Disease Specialist

PI on 2 active trials
DM
David Hansen, MD
Specialist
PI on 2 active trials
BM
Bernard Cohen, MD
Specialist
PI on 1 active trial
CM
C. David Hansen, MD
Specialist
PI on 1 active trial
SP
Sancy A Leachman, MD, PhD
MURRAY, UT
Specialist
PI on 2 active trials

Treatment Centers

8 centers
🏥 NORD

Baylor College of Medicine Rare Disease Center

Baylor College of Medicine

📍 Houston, TX

🏥 NORD

Stanford Medicine Rare Disease Center

Stanford Medicine

📍 Stanford, CA

🔬 UDN

NIH Clinical Center Undiagnosed Diseases Program

National Institutes of Health

📍 Bethesda, MD

🔬 UDN

UCLA UDN Clinical Site

UCLA Health

📍 Los Angeles, CA

🔬 UDN

Baylor College of Medicine UDN Clinical Site

Baylor College of Medicine

📍 Houston, TX

🔬 UDN

Harvard/MGH UDN Clinical Site

Massachusetts General Hospital

📍 Boston, MA

🏥 NORD

Mayo Clinic Center for Individualized Medicine

Mayo Clinic

📍 Rochester, MN

👤 Mayo Clinic Center for Individualized Medicine

🏥 NORD

UCLA Rare Disease Day Program

UCLA Health

📍 Los Angeles, CA

Travel Grants

No travel grants are currently matched to Pachyonychia congenita.

Search all travel grants →NORD Financial Assistance ↗

Community

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Latest news about Pachyonychia congenita

Disease timeline:

New trial: Efficacy and Safety of Bezafibrate 400 mg and Bezafibrate 200 mg as Adjunctive Treatments in Patient

Phase PHASE3 trial recruiting. Bezafibrate 400 mg in addition to UDCA therapy

Caregiver Resources

NORD Caregiver Resources

Support, advocacy, and financial assistance for caregivers of rare disease patients.

Mental Health Support

Rare disease caregiving can be isolating. Connect with counseling and peer support.

Family & Caregiver Grants

Financial assistance programs specifically for caregivers of rare disease patients.

Social Security Disability

Learn how rare disease patients may qualify for SSDI/SSI benefits.

Common questions about Pachyonychia congenita

What is Pachyonychia congenita?

Pachyonychia congenita (PC) is a rare genetic disorder of keratinization that primarily affects the nails, skin, oral mucosa, and other ectodermal tissues. It is caused by mutations in genes encoding keratin proteins (KRT6A, KRT6B, KRT6C, KRT16, and KRT17) that are essential for the structural integrity of epithelial cells. The condition was historically classified into two main types — PC-1 (Jadassohn-Lewandowsky type) and PC-2 (Jackson-Lawler type) — but is now more commonly categorized by the specific gene affected (e.g., PC-K6a, PC-K6b, PC-K16, PC-K17). The hallmark features of pachyonych

How is Pachyonychia congenita inherited?

Pachyonychia congenita follows a autosomal dominant inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.

At what age does Pachyonychia congenita typically begin?

Typical onset of Pachyonychia congenita is neonatal. Age of onset can vary across affected individuals.

Are there clinical trials for Pachyonychia congenita?

Yes — 2 recruiting clinical trials are currently listed for Pachyonychia congenita on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.

Which specialists treat Pachyonychia congenita?

7 specialists and care centers treating Pachyonychia congenita are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.